I commute to work on a Marin San Rafael on roads over a mix of flat to steep roads. My bike came with "700 x 35c with Puncture Protection" semi-slick tires:

In the bike shed at work I noticed another bike had slick tires, without any tread. After doing a little research online I found these tires:

I'm wondering whether or not it's worth changed my existing tires for these. My main desire is faster, easier riding on the road. Will these (or similar) tires provide less rolling resistance over the default tires I already have?

Do you know what the specific model of tire you have now is? From what I could find looking online it looked like it might be the Vittoria Adventure 700x35, which really doesn't have much of a tread to it.
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freiheit♦Oct 31 '10 at 1:21

but how much tread do your current tires actually have? Does it look more like knobs added on, or small grooves cut into the tire? Knowing those things helps to figure out how effective changing your tires out really would be. Does it look like this: vittoria.com/wp-content/uploads/2010/07/adventure.jpg ?
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freiheit♦Oct 31 '10 at 18:55

1

@freiheit I've taken a photo of my current tires and added it to my original question
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Peter BridgerNov 3 '10 at 17:02

3

If you're commuting, Conti Gatorskins, Specialized Armadillos, Soma Everwears, et al. are a must, must must. I've gone car-free for periods of about a year, and blew at least a dozen tubes before riding sucking up the US$30/tire price of these, which have paid for themselves many times over.
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MarcNov 8 '10 at 2:08

7 Answers
7

Yes, definitely -- if you're riding on mostly paved roads, switch to bald-ish tires. Rolling resistance is huge and equates directly to effort, though as you start going really fast it is dwarfed by air and gravity of course. Per the graph here:

However, one caution: road tires tend to be skinny, and you probably want fat-but-bald tires instead. If you go from a 35mm wide treaded tire to a 25mm bald tire, you will feel a lot more bumps.

So in summary: bald, for sure, but don't sacrifice too much width/comfort in the process.

You will notice a significant difference immediately by moving to a proper road tire. Unless you are doing significant amounts of riding of that bike on dirt or mud, you are better off going with the gators. Those tires are pretty tough and will do well even if you have some of your commute on gravel. (I have these on my commuter bike)

All the above answers are seriously off in their estimation of the effect it will have on your speed. Going from semi-slick tires, like the ones pictured, to even very narrow slick tires will not improve your averages by more than 1-2 km/h.

The effect of rolling resistance on pavement is not "huge", it's dwarfed by air resistance, especially at higher speeds (air resistance increases in proportion to the square of speed, while rolling resistance increases linearly).

You can try to plug different rolling resistances into this model to see how little effect it will have on your average speed (and since you are on a trekking bike, your position's frontal area will be definitely closer to 0.7 than 0.4):
http://www.analyticcycling.com/ForcesSpeed_Page.html

You make some good points, but at commuter-bike speeds, the calculator you linked to shows that rolling resistance makes a huge difference. I set the frontal area to 0.7, slope to 0, and power to 100 watts. A coefficient of rolling resistance of 0.01 gave 14.1 miles per hour, while lowering it to 0.005 raised the speed to 15.7 miles per hour. That's a pretty big effect.
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amcnabbJul 8 '12 at 14:16

Now we are splitting hairs, but what do you exactly mean by commuter bike speeds? I see two different commuting approaches possible - either you absolutely avoid getting sweaty, and so you indeed ride at less than about 100 watts, or you don't, in which case you ride as fast as you can (probably about 160-200W for an untrained male in OK shape). In the former case it's true that rolling resistance is of relatively bigger importance. But as the OP cares about speed, I suspect we are rather talking about the latter approach.
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ttarchalaJul 9 '12 at 20:19

3

I agree that this is an important distinction. But even at 200 watts, the change from 0.01 to 0.005 raised the speed from 19.3 mph to 20.5 mph. It may not be a huge difference, but reaching that speed on the slower tires would require increasing the power to 233 watts. The benefit would be enough for a rider to notice and appreciate.
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amcnabbJul 9 '12 at 20:51

This summer I switched from pretty nobby tires on my mountain bike to slicks. I was doing a longer overnight trip with a friend and wanted to put in a little less effort. I found that I could go so much faster with slicks that the gearing on my bike was bordering on being too slow. Just shows what a bit difference swapping out the tires does.

Here is one counter argument about swapping out your tires. After you switch to slick tires, going the same distance, you will exert much less energy. If you are cycling for exercise and only want to go a certain distance you will get a better workout with studdy tires.